The effect of storage on full blood count in different anticoagulants

Abstract

Background: The effect of storage on full blood count in different anticoagulant was determined in view of its importance on the reliability and validity of test results as the quality of sample stored would determine the quality of results.
Methodology: A total of twenty-five samples of apparently healthy individual were assessed for their Packed cell volume (PCV), total leucocytes count (TLC), platelets count and blood cell morphology by storing 2mls each of their blood sample in Ethylenediamine tetra acetic acid (EDTA), trisodium citrate, lithium heparin, fluoride oxalate and CPDA anticoagulants for a period of 24hrs, 48hrs 72hrs, and 96hrs at 40C to determine any changes that would occur.
Result: The PCV record a higher result (35.18 - 40.02%) with statistically significant different PCV of sample in EDTA, CPDA and those in trisodium citrate, lithium heparin (P< 0.05). Fluoride oxalate and trisodium citrate had more degenerative changes on the red blood cell morphology than EDTA and CPDA, Lithium heparin showed significant changes for white blood cell count, mild thrombocytopenia was found in samples stored after 72hrs in all anticoagulant as compared with initial platelet estimate at the time of collection. On the other hand, no significant changes of white blood cell morphology occurred after their storage in all anticoagulant except fluoride oxalate. The result showed more degenerative changes in fluoride oxalate, trisodium citrate and lithium heparin than CPDA and EDTA. Samples stored for 24 hours at 40C would not result in significant changes in blood parameters.
Conclusion: Based on these findings EDTA is the recommended anticoagulant of choice for haematological work and storage of specimen for analysis should not be encouraged as it adversely affects full blood count. Also, haematological laboratories are advised not to keep samples beyond 24 hours at 40C for reliability of test results.